Apparatus for cleaning pipe lines



1964 2. 0. ST. PALLEY APPARATUS FOR CLEANING PIPE LINES 2 Sheets-Sheet 1 Filed Jan. 17, 1963 aozm 0.

1964 2. 0. 5T. PALLEY APPARATUS FOR CLEANING PIPE LINES 2 Sheets-Sheet 2 Filed Jan. 17, 1963 United States Patent Ofi ice 3,il8,45 6 Patented Jan. 21, 196-4 3,118,456 APPARATUS FOR CLEANING PIPE LINES Zoltan 0. St. Palley, Hotchkiss Grove, Branford, Conn. Filed Jan. 17, 1963, Ser. No. 252,106 4 Claims. (Cl. 134-57) My invention relates to apparatus for cleaning pipe lines and other equipment by means of a periodically reversed flow of cleaning fluid.

In the apparatus of this type actuated by compressed air one of the problems is the loss of cleaning fluid caused by the fact that, at the end of transfer cycle the exhaust air carries considerable amount of cleaning fluid, in the form of a spray, into the outside atmosphere. As this loss occurs at each transfer cycle it can affect seriously the economy of the operation; in some cases the spray of the cleaning solvent may be even harmful to the personnel attending the apparatus.

One of the principal objects of my invention is to eliminate this solvent loss by providing a cleaning apparatus for pipe lines in which this spray of cleaning fluid ejected from the main tank is reclaimed and returned to the main tank for further use, entirely automatically, at the start of the next transfer cycle.

Another important object of my invention is to provide an apparatus for cleaning pipe lines in which the interior of the main tank and the outlet pipe, connecting the main tank to the pipe line to be cleaned, are totally free from moving parts or protruding elements or actuators, frequently found in the prior art machines of this type, thereby insuring a free passage of the cleaning fluid and an easier sanitary maintenance of the machine.

A further object of my invention is to provide a pneumatic apparatus for cleaning pipe lines in which each transfer of the cleaning fluid is actuated by a measured volume or" high pressure air with a full utilization of its expansive power. This facilitates the adjustment of the apparatus so as to attain the best economy in the air consumption.

Other objects and advantages of my invention will be apparent during the course of the following description.

in the accompanying drawing, forming a part of the present application, wherein for the purpose of illustration is shown a preferred form of my invention,

FIGURE 1 is a diagrammatic view of my apparatus,

FIGURE 2 is a longitudinal sectional view of my spray reclaiming tank and spray sensor,

FIGURE 3 is a cross sectional view of said spray reclaiming tank and the spiral batfle plate.

Referring to the drawings, in FIG. 1 the numeral 1 designates the article to be cleaned by the apparatus which, in this case is a pipe line, the ends of which are con nected to the outlet pipes 3 and 163 of the tanks 2 and 102, respectively.

As the present apparatus consists of two duplicate units the description of one unit will be sufficient for the understanding of this invention.

The tank 2, called the main tank, has a cylindrical body with an air-tight cover and a conical bottom adjoining the output pipe 3. Leading into the upper portion of the tank 2 are two pipes: the exhaust pipe 4 and the air intake pipe 6; the former is equipped with a directional valve permitting a flow out of the tank 2, the latter has a similar directional valve 7 permitting a flow into the tank 2, as indicated by the arrows.

An important element of my invention is the spray reclaiming tank 8, which is cylindrical in shape with an airtight cover. Mounted on this cover is the spray sensor 9. The construction of these elements is shown in FIGS. 2 and 3.

The spray reclaiming tank 8 communicates with the main tank 2 by the air intake pipe 6 leading to the base of the tank 8, and by the exhaust pipe 4 leading into a T-shaped fixture 40 mounted on the cover of the tank 8, which forms a part of the spray sensor. This fixture 40 has an extension 41, of tubular shape, passing through the cover into the interior of the tank 8 and having an opening 42 near its end. Mounted around this tubular exten sion 4i is the baffle plate 44 which, in this preferred form has a spiral design. The upper end of this spiral baffle plate 44 contacts the cover of the tank 8; the lower end of the spiral baflle plate 44 is closed up by the plate 43. The function of this baffle plate is the separation of the fluid of the spray from the air.

The spray sensor 9, the sectional view of which is shown in FIG. 2, has two opposing air chambers communicating with the T-shaped fixture 40 through the tubes 45 and 46, respectively, and are enclosed by the elastic diaphragms 48 and 47, respectively. These diaphragms rest on the pistons 49 and 50, respectively. These pistons are slidable and are connected together by a central part which is pivotally connected to the lever 51, so that the sliding of the pistons 49 and 50 will swing the lever 51 between the full line and the dotted line positions, shown in FIG. 2. The spring 52, the tension of which is adjustable by the screw and nut 53, tends to keep the lever '51 in the full line position. The numeral 10 represents a normally open switch, with terminals '55 and 56. This switch is so positioned that, when the lever 51 moves into the dotted line position it closes the switch.

The important feature of the spray sonsor is that the sensor tubes 45 and 46 have different shape and arrangement; the former is straight with an entrance opening tangentially arranged with respect to the flow coming from the exhaust pipe 4, whereas the tube 46 is bent with the entrance opening facing the stream coming from the pipe 4. As a result of this arrangement the impact of the flow at the entrance of the tube 46 will build up a pressure difference whereby the force acting on the diaphragm 47 will be greater than the force acting on the diaphragm 48. This pressure difference tends to move the pistons and the connected lever 51 from its full line position toward its dotted line position. The magnitude of this pressure difference depends on the density of the flow. The tension of the spring 52 is so adjusted that, when the exhaust flow coming out of the pipe 4 consists principally of air, the resultant pressure diiference is not sufficient to move the lever 51 against the tension of the spring 52. When, however, the exhaust air from pipe 4 carries a predetermined amount of cleaning fluid particles, in the form of a spray, the resultant greater pressure difference will overcome the tension of the spring 52 and will move the lever 51 into the dotted line position, causing thereby the closing of the switch It). It is to be noted that the static air pressure, existing in the tanks 2 and 8 or in the pipes 4 and 6, has no effect on the operation of the spray sensor 9, because in a static condition the forces acting on the iaphragms 47 and 48 are equal and opposite in direction.

Communicating with tank 8 through the pipe 13 are the air intake valve 11 and the exhaust valve 12, shown in FIG. 1. These valves are solenoid operated and are open when the solenoid is energized and closed when the solenoid is deenergized. Pipe 15 brings the compressed air supply to the air intake valve 11 and pipe 14 conducts the exhaust air from the exhaust valve 12. r

The opening and the closing of the valves 11 and 12, and the resultant periodic reversal of the flow of the cleaning fluid is accomplished by the relays 19, 21, 23, 25, actuated by the solenoid 18, 20, 22, 24, respectively. These solenoids receive energy from the electrical supply terminals 31 and 32, through the manual switch 26, and they are so constructed that when the solenoids are energized the corresponding relays move into the dotted line position, and when the solenoids are deenergized said relays automatically return into their full line position. The electrical connections between said relays and the cooperative elements of the apparatus are shown in FIG. 1. The corresponding elements in the duplicate unit of the apparatus are designated by the same numerals plus 100. It is to be noted that the control circuits of the two duplicate units are interconnected by the pilot lines 29 and 30 for the purpose of coordinating the operation of the two units.

Another important element of my invention is the air economizer 16, shown in FIG. 1, the function of which is to measure and limit the compressed air volume, admitted into the tank in each transfer cycle, in order to permit the utilization of the expansive power of the compressed air and thereby attain a greater economy in the air consumption of the apparatus. In the preferred form of my invention, illustrated in FIG. 1, this air economizer 16 consists of a small tank in communication with the main tank 2, containing a float which is connected to the switch 17 in such a manner that when the float assumes its lowest position, due to the absence of liquid, it moves the switch 17 into the full line position, shown in FIG. 1, causing, through the relay 19, the closing of the air intake valve 11. Though used for a different purpose, the air economizer 16 has the construction of a liquid level indicator, of which several types are known in the art, some of them being floatless. It is within the spirit of my invention to employ any of these known types of liquid level indicators as air economizers, provided they can actuate a switch or equivalent pneumatic or hydraulic device in their empty position.

It is a fundamental feature of my air economizer that the height of its position in relation to the main tank 2 is variable and usually easily adjustable so as to permit the admittance of a specified volume of compressed air into the main tank for each transfer cycle. In order to facilitate this adjustability, the communication between the air economizer and the main tank is obtained by the use of flexible tubing or hoses.

The operation of my invention is as follows: The first step is to fill the tank 2 with cleaning fluid; then, the switch 26 is closed, permitting the current to flow through the full line contacts of the relay 22 to the relay 19. Here the current is divided into two parts, one part will flow through the full line contacts of the relay 19 to the solenoid of the air intake valve 11, causing the opening of this valve. The other part of this current will flow through the pilot line 30 to the other unit, causing the energization of solenoid 122, causing the relay 123 to move into its dotted line position.

The next step is to close the switch 126, permitting the current to flow through the dotted line contacts of the relay 123 into the solenoid of the exhaust valve 112, causing the opening of this valve. The apparatus is now ready for the transfer of the cleaning fluid from the tank 2 into the tank 102.

The next step is to connect the pipes 15 and 115 with the compressed air supply. As the air intake valve 11 is open, the air coming in through pipe 15 will flow through the spray reclaiming tank 8 and the pipe 6 into the upper part of the tank 2 forcing the cleaning fluid from the tank 2 into the tank 102 through the pipe line 1. The air displaced by the coming fluid in the pipe line and in the tank 102 will find exit through the pipe 104, the tank 108, pipe 113 and the open exhaust valve 112. The entrance of the compressed air through the valve 11 is continued until the level of the fluid in the tank 2 is lowered to the level corresponding to the empty position of the air economizer 16. At this level of the fluid the switch 17 moves into its lower position, indicated by the full line in FIG. 1, with the result that the current flowing through the switch 26 will now flow through the switch 17 into the solenoid 13, causing the swinging of the relay 19 into its dotted line position, interrupting the encrgization of the air intake valve 11 received from the relay 23, and thereby closing the valve 11.

We have now a measured volume of high pressure air enclosed in the tank 2 and will utilize the expansive force of this air for the completion of the transfer of the fluid into the tank 102. During this period of expansion the driving force acting on the moving fluid is gradually decreasing, due to the decreasing of the air pressure in the tank 2, this, however, is quite permissible as after the acceleration of the fluid is accomplished the power re quirement of the transfer is also decreasing. This uti' lization of the expansive power of the compressed air has two important advantages: a material reduction of the air consumption and a smoother operation of the apparatus due to the easier deceleration of the moving fluid and the lower pressure of the exhaust air.

During the transfer of the fluid the air displaced by the incoming fluid escapes through the pipe 104 into the spray reclaiming tank 108, which is a duplicate of the device illustrated in FIGS. 2 and 3. This flow of air will cause a pressure difference in the spray sensor 109 which will be, however, too small to overcome the spring pressure of the spray sensor and therefore, cannot actuate the switch 110. When, however, the transfer of the fluid is completed and the high pressure air, back of the column of fluid, wili reach the bottom opening of the tank 102, this air will rise very rapidly through the fluid within the tank 102 causing violent bubbling and a dense spray. When this spray, escaping through the pipe 104, strikes the spray sensor 109 it will overcome the tension of the spring of the spray sensor and will close the switch 110, causing the reversal of the fluid transfer in the following manner: The air economizer tank 116 being full, the switch 117 will be in the full line position and will conduct the current coming from the switch 126 to the solenoid 124, through the closed switch 110 and the full line contacts of the relay 121, causing the relay 125 to move into the dotted line position, thereby interrupting the energizing current of the solenoid 122 coming from the pilot line 30 and causing the relay 123 to move into the full line position, shown in FIG. 1. This movement of the relay 123 will deenergize and close the exhaust valve 112, will energize and open the intake valve 111, will also send a current through the pilot line 29 to the other unit, which through the relay 25 will flow into the solenoid 22, energizing it and thereby moving the relay 23 into the dotted line position. This movement of the relay 23 will deenergize and close the intake valve 11 and will energize and open the exhaust valve 12. Having completed the reversal of the positions of the valves 11, 12, 111 and 112, the compressed air will now enter through the intake valve 111 to force the cleaning fluid from the tank 102 back to the tank 2 and the valve 12 will now provide exit for the air displaced by the coming fluid column.

This reverse transfer cycle will have the same phases as the one just described: a power phase, during which a predetermined volume of compressed air will be admitted into the tank 102, the magnitude of which will depend on the height of the position of the air economizer 116, and an expansion phase, during which the expansive power of the compressed air enclosed in the tank 102 will be utilized to complete the transfer of the fluid into the tank 2. At this instant the spray sensor 9 will come into action. As a result of the special arrangement of the sensor tubes 45 and 46 (see FIG. 2), the heavy spray carried by the exhaust air will produce a pressure difference on the opposed diaphragms 47 and 48, of suflicient strength to close the switch 10 thereby causing the reversal of the positions of the valves 11, 12, 111, and 112 controlling the direction of the fluid transfer.

One of the important and novel features of my invention is the reclaiming of the cleaning fluid carried out by the exhaust air. This is accomplished in the following manner: As shown in FIGS. 2 and 3, the exhaust stream coming in through the pipe 4 is diverted downwardly into the tube 41 and escapes through the side opening 42, the end of the tube 41 being closed by the plate 43. Here the exhaust stream meets the spiral baffle plate 44 and assumes a fast rotary motion, with the result, that due to the combined effect of the centrifugal force and the gravity the fluid is separated from the air. The fluid flows down on the inner surface of the spiral baffle and is collected in the tank 8, whereas the air rises and escapes through the pipe 13 to the open exhaust valve 12. At the start of the next transfer cycle the compressed air coming from the open intake valve 11 will enter the spray reclaiming tank 8 through the pipe '13 and will force the fluid collected in the tank 8 through the pipe 6 back to the main tank 2 for future utilization, as the directional valve 5 blocks the passage toward the tank 2 in the pipe 4. In alternative forms of my invention the baflle may have various other shapes known in the art, instead of the spiral shape employed in the preferred form illustrated.

It is also within the spirit of the present invention to substitute equivalent pneumatic or hydraulic circuits, actuating and actuated elements for the electric circuits, solenoids, relays and switches employed in the preferred form described and illustrated herein. In alternative forms of my invention the intake and exhaust valves 11, 111i and 12, 112, may be operated by pneumatic or hydraulic cylinders and pistons, instead of solenoids, the actuating switches 10, 110 and 1'7, 117 replaced by valves, the relays 1824 and ;118--124 replaced by piston operated valves, operatively interconnected by pneurnatic or hydraulic piping, replacing the electrical wiring shown in FIG. 1. The equivalency of certain electrical, pneumatic and hydraulic circuits and elements is recognized in the art, therefore, the term pilot circuit means includes all alternative forms where the electrical elements shown and described herein are replaced by equivalent pneumatic or hydraulic means.

It is to be understood that the form of my invention herein described and illustrated is only an example of the same and that various changes in the shape, size, and arrangement of the parts may be resorted to, without departing from the spirit of my invention or the scope of the subjoined claims.

I claim:

1. An apparatus for cleaning a pipe line comprising a pair of closed tanks for holding the cleaning fluid, each having an outlet pipe connected to opposite ends of the pipe line; a compressed air supply; a pair of air intake valves, having open and closed positions, each of said intake valves communicating with said air supply and with one of said tanks to admit compressed air, alternately, to one of the tanks in order to force the cleaning fluid through the pipe line into the other tank; a pair of exhaust valves, having open and closed positions, each communicating with one of said tanks for the exhaust of air; pilot circuit means operatively interconnecting said valves; a pair of spray reclaiming means, each communicating with one of said tanks and having baflle means adapted to separate and retain the fluid carried by the exhaust air from said tank, and having also directional valve means adapted to conduct said retained fluid back to said tank when forced by the compressed air coming from said intake valves; a pair of spray sensors, each communicating with one of said tanks and the correspending spray reclaiming means and being operatively connected with said pilot circuit means, said spray sensor means being adapted to measure the pressure difference in the exhaust stream coming from said communicating tank caused by dynamic impact and to actuate said pilot circuit means, when said pressure difference reaches a predetermined magnitude, so as to reverse the positions of the said intake and exhaust valves, and thereby reverse the transfer of said cleaning fluid.

2. The apparatus of claim 1 which comprises a pair of air economizers, each communicating with one of said tanks and being operatively connected said pilot circuit means, and being adapted to limit the compressed air admitted into the communicating tank to a predetermined volume, as measured by the level of the fluid in said tank, in order to utilize the expansive power of said air.

3. The apparatus of claim 2 in which :the pilot circuit means operatively interconnecting the various elements consists of electrical means.

4. In an apparatus for cleaning a pipe line having a pair of closed tanks for holding fluid, a pair of intake valves, each for admitting air into one of said tanks, a pair of exhaust valves, each for exhausting air from one of said tanks, said valves having open and closed positions, and pilot circuit means adapted to change the positions of said valves, the combination comprising an intake pipe with directional valve means adapted to conduct air into one of said tanks, but prevent a flow in the opposite direction; an exhaust pipe with directional valve means adapted to conduct exhaust from the same tank, but prevent a flow in the opposite direction; a spray reclaiming means lfOl' receiving the exhaust of the same tank, and having baflie means separating and retaining the fluid carried in the exhaust, also having three openings: a top opening receiving exhaust from said exhaust pipe, an intermediate opening communicating with said valves of the same tank, and a bottom opening communicating with the intake pipe of the same tank, so as to conduct said separated and retained fluid back to said tank when said fluid is forced by pressure of the air coming in through said intermediate opening of the spray reclaiming means; a spray sensor having a passage inserted between said exhaust pipe and said top opening of the spray reclaiming means for conducting the flow of exhaust coming from said tank; two spray sensor tubes communicating with said flow of exhaust, one having its entrance opening facing said exhaust flow, the other having its entrance opening tangential to said exhaust flow, said sensor tubes communicate with two opposing flexible diaphragms, transmitting to them pressures, the difference of which is a function of the mechanical impact of the exhaust flow; indicating means operatively connected with said diaphragms and said pilot circuit means, and being adapted to actuate said pilot circuit means so as to change the positions of said valves when said difference of the pressures acting on said diaphragms reaches a predetermined magnitude.

References Cited in the file of this patent UNITED STATES PATENTS 

1. AN APPARATUS FOR CLEANING A PIPE LINE COMPRISING A PAIR OF CLOSED TANKS FOR HOLDING THE CLEANING FLUID, EACH HAVING AN OUTLET PIPE CONNECTED TO OPPOSITE ENDS OF THE PIPE LINE; A COMPRESSED AIR SUPPLY; A PAIR OF AIR INTAKE VALVES, HAVING OPEN AND CLOSED POSITIONS, EACH OF SAID INTAKE VALVES COMMUNICATING WITH SAID AIR SUPPLY AND WITH ONE OF SAID TANKS TO ADMIT COMPRESSED AIR, ALTERNATELY, TO ONE OF THE TANKS IN ORDER TO FORCE THE CLEANING FLUID THROUGH THE PIPE LINE INTO THE OTHER TANK; A PAIR OF EXHAUST VALVES, HAVING OPEN AND CLOSED POSITIONS, EACH COMMUNICATING WITH ONE OF SAID TANKS FOR THE EXHAUST OF AIR; PILOT CIRCUIT MEANS OPERATIVELY INTERCONNECTING SAID VALVES; A PAIR OF SPRAY RECLAIMING MEANS, EACH COMMUNICATING WITH ONE OF SAID TANKS AND HAVING BAFFLE MEANS ADAPTED TO SEPARATE AND RETAIN THE FLUID CARRIED BY THE EXHAUST AIR FROM SAID TANK, AND HAVING ALSO DIRECTIONAL VALVE MEANS ADAPTED TO CONDUCT SAID RETAINED FLUID BACK TO SAID TANK WHEN FORCED BY THE COMPRESSED AIR COMING FROM SAID INTAKE VALVES; A PAIR OF SPRAY SENSORS, EACH COMMUNICATING WITH ONE OF SAID TANKS AND THE CORRESPONDING SPRAY RECLAIMING MEANS AND BEING OPERATIVELY CONNECTED WITH SAID PILOT CIRCUIT MEANS, SAID SPRAY SENSOR 